Exelixis, Inc.NASDAQ: EXEL

Exelixis Announces Positive Phase 2 Results for CABOMETYX® (cabozantinib) in Combination with OPDIVO® (nivolumab) in Patients with Metastatic Non-Clear Cell Renal Cell Carcinoma at ASCO 2021

· Issued by Exelixis, Inc. via Business Wire

– CABOMETYX in combination with OPDIVO demonstrated an objective response rate of 47.5% in a cohort of patients with certain histologies of advanced or metastatic nccRCC –

– Data to be presented during the 2021 American Society of Clinical Oncology’s Annual Meeting –

ALAMEDA, Calif.--(BUSINESS WIRE)-- Exelixis, Inc. (NASDAQ: EXEL) today announced promising phase 2 results for CABOMETYX® (cabozantinib) in combination with Bristol Myers Squibb’s OPDIVO® (nivolumab) in patients with advanced or metastatic non-clear cell renal cell carcinoma (nccRCC) from an investigator-sponsored trial. The combination regimen showed promising efficacy and an acceptable safety profile in patients with metastatic nccRCC with papillary, unclassified or translocation-associated histologies. The data will be presented as part of the Poster Discussion Session: Genitourinary Cancer – Kidney and Bladder at the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting, which is being held virtually, June 4-8, 2021. All posters will be available on demand beginning at 6:00 a.m. PT on Friday, June 4.

“The strong objective response rate associated with cabozantinib in combination with nivolumab in this trial is a meaningful finding for this patient community, who are typically not the focus of major clinical trials for kidney cancer,” said Dr. Chung-Han Lee, medical oncologist at Memorial Sloan Kettering Cancer Center, and principal investigator for the study. “We look forward to building on these results with additional insights into which types of non-clear cell renal cell carcinoma may be most likely to respond to this combination regimen.”

This single-institution, non-randomized, open-label, investigator-sponsored, phase 2 trial of CABOMETYX 40 mg in combination with OPDIVO (240 mg every two weeks or 480 mg every four weeks) was conducted by Memorial Sloan Kettering Cancer Center. The trial enrolled patients with advanced or metastatic nccRCC who had not received prior immune checkpoint inhibitor (ICI) therapy. A total of 47 patients were treated; 40 patients with papillary, unclassified, or translocation-associated RCC in cohort 1, and seven patients with chromophobe histology in cohort 2. Median follow-up was 13.1 months.

In cohort 1, CABOMETYX in combination with OPDIVO demonstrated an objective response rate (ORR) of 47.5% (95% confidence interval [CI]: 31.5–63.9). Among the 32 patients with papillary histology, ORR was 47% (95% CI: 29–65). Objective responses were seen in five of six patients with NF2 mutations, four of five patients with FH mutations and one of six patients with SETD2 mutations. Median duration of response was 13.6 months. Median progression-free survival was 12.5 months (95% CI: 6.3–15.9), and median overall survival was 28 months (95% CI: 16.3–non-estimable). A best response of stable disease was observed for five of seven patients in cohort 2.

“Following the recent FDA approval of CABOMETYX in combination with OPDIVO as a first-line treatment for patients with advanced renal cell carcinoma, we’re excited to see these new data specifically in non-clear cell RCC, a heterogeneous group of kidney cancers,” said Gisela Schwab, M.D., President, Product Development and Medical Affairs and Chief Medical Officer, Exelixis. “These positive phase 2 results build on our understanding of CABOMETYX’s potential use in papillary RCC, one of these subtypes, and may help physicians choose an appropriate first-line systemic therapy for their patients with advanced non-clear cell renal cell carcinoma.”

CABOMETYX or OPDIVO was discontinued due to adverse events in 17% and 13% of patients, respectively. Both therapies were discontinued due to adverse events in 9% of patients. Grade 3/4 treatment-related adverse events were observed in 32% of patients. The most common grade 3/4 treatment-related adverse events were hypertension (13%) and diarrhea (6%).

More information about this trial (NCT03635892) is available at ClinicalTrials.gov.

About RCC

The American Cancer Society’s 2021 statistics cite kidney cancer as among the top ten most commonly diagnosed forms of cancer among both men and women in the U.S.1 If detected in its early stages, the five-year survival rate for RCC is high; for patients with advanced or late-stage metastatic RCC, however, the five-year survival rate is only 13%.1 Approximately 32,000 patients in the U.S. and 71,000 worldwide will require systemic treatment for advanced kidney cancer in 2021.2

About 70% of RCC cases are known as “clear cell” carcinomas, based on histology.3 Other subtypes, collectively grouped as nccRCC, constitute a diverse mixture of malignancies.4 Papillary histology accounts for about 15% of all renal cell carcinomas.5,6 Genomic and molecular characterization of papillary RCC has implicated MET signaling as a key driver of this cancer.6,7 Targeting VEGFR and other tyrosine kinases, including MET and AXL, has led to improved outcomes in RCC compared with sunitinib and further supported the investigation of MET-targeting tyrosine kinase inhibitors in nccRCC.

About CABOMETYX® (cabozantinib)

In the U.S., CABOMETYX tablets are approved for the treatment of patients with advanced RCC; for the treatment of patients with HCC who have been previously treated with sorafenib; and for patients with advanced RCC as a first-line treatment in combination with OPDIVO. CABOMETYX tablets have also received regulatory approvals in the European Union and additional countries and regions worldwide. In 2016, Exelixis granted Ipsen exclusive rights for the commercialization and further clinical development of cabozantinib outside of the United States and Japan. In 2017, Exelixis granted exclusive rights to Takeda Pharmaceutical Company Limited for the commercialization and further clinical development of cabozantinib for all future indications in Japan. Exelixis holds the exclusive rights to develop and commercialize cabozantinib in the United States.

IMPORTANT SAFETY INFORMATION

WARNINGS AND PRECAUTIONS

Hemorrhage: Severe and fatal hemorrhages occurred with CABOMETYX. The incidence of Grade 3 to 5 hemorrhagic events was 5% in CABOMETYX patients in RCC and HCC studies. Discontinue CABOMETYX for Grade 3 or 4 hemorrhage. Do not administer CABOMETYX to patients who have a recent history of hemorrhage, including hemoptysis, hematemesis, or melena.

Perforations and Fistulas: Fistulas, including fatal cases, occurred in 1% of CABOMETYX patients. Gastrointestinal (GI) perforations, including fatal cases, occurred in 1% of CABOMETYX patients. Monitor patients for signs and symptoms of fistulas and perforations, including abscess and sepsis. Discontinue CABOMETYX in patients who experience a Grade 4 fistula or a GI perforation.

Thrombotic Events: CABOMETYX increased the risk of thrombotic events. Venous thromboembolism occurred in 7% (including 4% pulmonary embolism) and arterial thromboembolism in 2% of CABOMETYX patients. Fatal thrombotic events occurred in CABOMETYX patients. Discontinue CABOMETYX in patients who develop an acute myocardial infarction or serious arterial or venous thromboembolic events that require medical intervention.

Hypertension and Hypertensive Crisis: CABOMETYX can cause hypertension, including hypertensive crisis. Hypertension was reported in 36% (17% Grade 3 and 3 times ULN (Grade ≥2) was reported in 83 patients, of whom 23 (28%) received systemic corticosteroids; ALT or AST resolved to Grades 0-1 in 74 (89%). Among the 44 patients with Grade ≥2 increased ALT or AST who were rechallenged with either CABOMETYX (n=9) or nivolumab (n=11) as a single agent or with both (n=24), recurrence of Grade ≥2 increased ALT or AST was observed in 2 patients receiving CABOMETYX, 2 patients receiving nivolumab, and 7 patients receiving both CABOMETYX and nivolumab.

Adrenal Insufficiency: CABOMETYX in combination with nivolumab can cause primary or secondary adrenal insufficiency. For Grade 2 or higher adrenal insufficiency, initiate symptomatic treatment, including hormone replacement as clinically indicated. Withhold CABOMETYX and/or nivolumab depending on severity.

Adrenal insufficiency occurred in 4.7% (15/320) of patients with RCC who received CABOMETYX with nivolumab, including Grade 3 (2.2%), and Grade 2 (1.9%) adverse reactions. Adrenal insufficiency led to permanent discontinuation of CABOMETYX and nivolumab in 0.9% and withholding of CABOMETYX and nivolumab in 2.8% of patients with RCC.

Approximately 80% (12/15) of patients with adrenal insufficiency received hormone replacement therapy, including systemic corticosteroids. Adrenal insufficiency resolved in 27% (n=4) of the 15 patients. Of the 9 patients in whom CABOMETYX with nivolumab was withheld for adrenal insufficiency, 6 reinstated treatment after symptom improvement; of these, all (n=6) received hormone replacement therapy and 2 had recurrence of adrenal insufficiency.

Proteinuria: Proteinuria was observed in 7% of CABOMETYX patients. Monitor urine protein regularly during CABOMETYX treatment. Discontinue CABOMETYX in patients who develop nephrotic syndrome.

Osteonecrosis of the Jaw (ONJ): ONJ occurred in